Enforcement regulations under tax laws require that original transaction slips, such as receipts and billing statements forming the basis of records in accounting books retained by a company as a tax payer, be maintained for at least a predetermined period of time in storage such as in a storage site like corrugated cardboard boxes and file cabinets in a warehouse. When accounting books are checked for improper or fraudulent recording, the original transaction slips such as receipts and billing statements are searched and therefore, are removed from storage for collation with the records in the accounting books.
According to a related technique, for example, a manuscript is read in as an image that is subject to optical character recognition and searched, whereby a character string that is hit by a search keyword is retrieved. A highlighting process is applied to the position of the character string in the manuscript, and the result of the highlighting process is printed superimposed on the manuscript. For example, according to another technique, number information to identify an address card to be searched for is input by a user operation, the number information of plural address cards is read in, and matching between the read in number information and the input number information is determined. According to another technique, a payment notice is read in using an overhead reader (OHR), a payment notice ID is identified based on the obtained image data, the payment notice type representing a processing class of the payment notice is determined based on the identified payment notice ID, and the payment notice type is printed on the back of the payment notice (see, e.g., Japanese Laid-Open Patent-Publication Nos. 2008-107462, 2002-240397, and 2003-162643).